CAP-switch oligo

Hi,
I have come across a product supplied as part of a Clontech cDNA
synthesis kit called the Cap-switch oligo. As far as I can tell it
causes the reverse transcriptase to switch stands on reaching the Cap
and copy the oligo sequence, thereby allowing the second strand
synthesis to include the true 5' end. Does anybody knowe any details
about this? For example is it just an oligo, if so what sequence? Is it
modified? If so how? In other words is there an alternative to ordering
it from Clontech such as making it in house. I realise there may be
patent problems.
Any information would be greatly appreciated.
Thanks,
Rob
--
Rob Brooksbank
**********************PLEASE NOTE: NEW ADDRESS**********************
The Sanger Centre
email: rab at sanger.ac.uk Wellcome Trust Genome Campus
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